One man stood up during the event's Q&A portion, expressing concern about climate change. Addressing it, the audience member said, should be an imperative to Christians commanded by the Bible to be stewards of the Earth.

"I always have problems when people come up and say the science is settled," said Santorum, a Republican presidential candidate and winner of the 2012 Iowa caucuses. "That's what they said about the world being flat. When someone says the science is settled you're not a scientist, because scientists never say the science is settled."

He added: "The idea that the science is settled, to me, tells me that this is political science, not real science."